Improvement in stop-valves



.'*lnitedj guinea @wat dimite.

J'EREMIAH A. MAEDEN, OE BOSTON, MASSACHUSETTS, ASSTGNOE To GEORGE M. GIB- soN AND THOMASv A. JOHNSTON, OE SAME PLACE.

Letters Patent N 98,510, dated January 4, 1870.

IMPROVEMENT IN"- STOP-VALVES.

v The Schedule referred to in these Letters Patent and making part of' the name.

To all to whom these presents s/Lall come:

Be it known that I, JEREMIAH A. MARD'EN, of Boston, in the county of Sulolk, and Commonwealth of Massachusetts, have made an invention of a new and useful Improvement in Steam-Enginery; and

do hereby declare'the following to be a'full, clear, and exact description thereof, due reference beinghad to theaccompanying drawings, making part of this specification, and in which- Figure 1 is a plan,

Figure 2, a longitudinal section, and

Figure 3, a transverse section of a cylindrical steamvalve, provided with my invention.

A cylindrical conical steam-valve is now very generally employed, in connection with governors of steam-engines, and such class of valves, while possessing many important advantages, have, likewise,

"their defects, prominent among which is the-liability .s'crew being passed through .a bracket or arm, making part of the valve-case, in suoli manner as to advance or retractthefvalve, which is left free to oscillate independently ofthe screw, as hereinafter explained.

In the drawings before alluded toas accompanying this specification, and which illustrate my invention, A denotes the box or case of a cylindrical steam-valve, such valve beingshown at b, and vits seat at c, such parts being constructed and combined in manner sim'- ilar to others in use. v

In carrying out my invention, I affix to the outer end of the box A, a curved standard or bracket, (l, while through the upper part of this standard I ,i pass a screw, e, provided with a suitable hand-wheel or head, and also vwith a check-nut, f, to prevent its retraction.

'lhis screw is disposed in axial alignment with the valve b and its stem g, such screw and valve-stem being connected by a suitable swivellingfjoint, which, while securing them fully together on all occasions, permits of rotations of the valve and its stem, with respect to the bracket, which is, ofcourse, stationary.

It willbe evident, from the above-mentioned arrangement of partsthat should it become necessary` to retract the valve b, such movement may be eiected by a corresponding retraction ot'. t-he screw e, or by continuing this retraction of the screw to a sufficient extent, the valve may be entirely removed from its case. l p.

The ease and celerity withl which a valve may be blown off, as it is` technically termed,'by means of my invention, renders it'one of value` vAnotherand important advantage of my invention results from the ease and celerity with which the valve mayalway's be perfectly iitted, should any wear occur.

Although, in the accompanying drawings, I have represented the connection of the valve-stein and the Ascrew e, as elected by means of a yoke, clasping'a head or collar, formed upon each, it will be apparent that various descriptions of swivelling-joiuts may be adopted for the purpose. v

I would remark that I do not wish to confine myself to the employment of the screw e, as a means of regulating the end-movement of the valve, as other mechanical devices may be adopted, which shall eect the desired object, such as a cam or eccentric.

What I claim, then, and desire to secure by Letters i `Patent of the United States, is-

Oonnecting the valve-stem with the screw-rod, or

other fdevice by which the end-movements of the valve are efected, by means of a swivel-joint, which,

while compelling the valve to follow the longitudinal movement of the screw or other device, will permit it to oscillate independently of the same, substantially as shown and 4set forth. y

. J EREMIAH A. MARDEN.

Witnesses FRED. CURTIS, EDWARD GRIFFITH. 

